This invention relates to an alarm device which operates upon the principle of differential vacuum. More particularly, the present invention relates to a device which employs an audible vibratory reed assembly, automatically activatable upon being subjected to a predetermined differential-vacuum energy level.
A variety of such devices, which incorporate vibratable reeds so as to render the device capable of producing basic sonic tones, are well known. See, for example, the U.S. Pat. No. 4,365,582 to Boyer et al, which has been assigned to the Assignee of this application.
Although it will be appreciated by those skilled in the art that the present invention is generally useful for sounding an alarm whenever a predetermined differential-vacuum condition exists between two points, the present invention will herein preferably be described as it is used in a clothes dryer.
The fact that most clothes dryers generate lint, which often affects dryer performance, is well known. During use of the '582 device as a lint alarm on a clothes dryer, for example, it has been observed that entrained lint can enter the '582 housing, become attached to a reed element thereof, and thereafter affect the tonal qualities of the reed element.
Accordingly, it is a general object of this invention to provide a novel and improved differential-vacuum signal (or alarm) device, used preferably in a lint-laden environment (such as is found in a clothes dryer).
A more specific object is to provide such a device, capable of reliable operation over a long period of time while serving as a lint buildup alarm.
A further object is to provide such a device having a reed element which is readily incorporatable into a clothes dryer and which is substantially isolated from clothes dryer lint.